Manufacture of pile fabrics



`lune 20, 1939. R w. KENT MANUFAQTURE OF PILE FABRICS Filed May 2, 1956 6,6 ATTOR N EY Patented .lune 2o, 1939 UNITED STATES PATENT OFFICE MANUFACTURE F PILE FABRICS Raymond W. Kent, Newton Highlands, Mass.

Application May 2, 1936, Serial No. 77,53

v 9 Claims.

This invention relates to the manufacture of pile fabrics in which the pile is adhesively attached to one surface of a fabric backing, and has particularly to do with the provision of improved methods of preparation-and treatment of the pile or flock to be attached to said backing, though it also-,includes the further steps in the manufacture of such pile fabrics. The invention is especially useful in the manufacture of pile of substantially uniform length, for the flock if too long and non-uniform will not sift readily and will ball up in the flock-applying process or mat unevenly on the adhesivelycoated fabric or other backing and, if too short, it will not embed deeply l5 Aenough in the vadhesive to provide adequate wear resistance.

Heretofore cotton and rayon asmade" and adhesively applied by the suede fabric trade to rubber coated fabric have been relatively short. for example, 1/,4"-1/5 long, and ground either in a high speed grinder with resultant injury to the fibres, and the production of uneven lengths, 7

much dust and fibre loss, or cut by a guillotine device which is relatively slow and costly, and, as a consequence, guillotine cutting has not been generally used. In the dry grinding as practiced, the reor explosive hazard is great and many serious dust explosions have resulted, for the fibre, cotton or rayon for example, ground at high speed is extremely fine and when thoroughly mixed with air (oxygen) an ideal combination is presented for an explosion, should a spark by chance be available.

' AIt is the object of this invention to provide an 35' improved method of providing a clean and relatively dustless libre in substantially uniform short lengths and without injury to or mashing of the ends of the same. The methodv includes the cutting and treating of fibres such as cotton,'rayon, or animal fibres such as wool, mohair, rabbits hair, silk, etc., to provide a flock, and all of which fibres, it has been discovered, may in accordance with this invention be successfully cut to substantially uniform lengths by passing the libres, as hereinafter described, in a fluent liquid carrying medium through a cutting device.

All of the above mentioned fibres, with the exception of cotton, may be wet-cut in an aqueous carrying medium, butwith cotton bre it has been found preferable, to prevent hydration, to cut it in some freely iiuent non-aqueous liquid medium, for example, kerosene, vegetable oil, or-other`suitable non-hydrating liquid carrying medium compatible with the libre. It isfound in practice 55V that with the wet-cutting of the fibres the ends thereof are substantially as cleanly cut as in the guillotine method and .are not injured,not crushed or mashed, asin the dry grinding method. Moreover, a uniform and -straighteriibred iiock is secured, presumably because of the tendency of .5 the long fibres to more'or less align themselves in the fluent or freely moving body of liquid as in the apparatus which I preferably employ. Another outstanding advantage of. my method of treatment'is that the .material thus .secured is l0 much cleaner,.-free from dust. Ihe cleaning may be enhanced by any' suitable cleaning fiuid or by the presence of arsmallamount of soap. The washing and scrubbing actionproduces a iiock freer from dirt which dirt, being either lighter or heavier than the fibres, tends to separate f rom the fibres and thus, if desired, may be readily removed from the liquid.v Thus there is produced a clean short cut flock of uniform length (for example, Vif'to MW) the fibres of which re- 1 tain substantially.their uniform physical and chemical characteristics.

In the drawing, which illustrates the method and a form ofapparatus vsuitable for practicing the samethe figure shows a frontk elevational g5' y view with various parts broken away for purg poses of clarity,

'Referring to the drawing there is shown at I a mixing-.tank havingvtherein a stirring impeller 2, which tank is connected through a valve -3 to a 30 cutting device generally'designated at l, said device comprising a `irusto-conical cutter mounted for-rotation as-shown having upon its exterior a. series of helical blades 5 which are rotated in closely adjusted relation with reference to a fixed series oflongitudinal blades 6, so as to provide therewith a shearing cut. The fluent mass of long iibres upon being mixed in the liquid in the tank I is passed through the cutting device I wherein the fibres are cut to shorter lengths and 40 thence through the valve 1 into a heat-jacketed lower tank B having therein an impeller 9 from which the iiock thus cut to a shorter length may either 'be withdrawn through the valve I0, or, if necessary, to. shorten it still further, pumped by means of the gear pump I'I and return line I2 vback into the tank I from which it vmay again be passed through the cutting device.

As a specific example of the treatment of libre, say rayon fibres or thread, which it is desired to reduce'to a length of say 1,55" or less, the following is given,-to the water in which there is added rayon fibre in the amount of .1 ounce pei pound of water and the cutting is carried on for the required period to reduce the fibre to said lei? 3th,

the period varying somewhat depending upon lthe rapidity of the flowv and circulation, and the setting of the moving and fixed elements of the device.

In addition to the reducing of the fibre to substantially uniform length, it may be and preferably is, dyed in the apparatus (preferably provided With aheat jacket as shown), thus providing a thorough mixing of the dye with the fibre material thus colored. The dye may either be added in thefirst instance to the water or other liquid in the mixer (preferably water in the case of rayon or non-aqueous liquid in the case of cotton) or later added. A further advantage of the wet-cutting in the device is that two or more previously colored flocks may be simultaneously cut, washed and combined, with or without aclditional dyeing, to produce a heather effect, red and green for instance, the mixing taking place during the cutting as herein set forth.

Though it is not essential for thc successful practice of the process of this invention, particularly where only short fibres are applied, it is sometimes desirable to subject long pile or fibres to a preliminary sizing treatment and thus temporarily render the fibres heavier, smoother and stiffer, forit has been discovered that fibres, especially the longer fibres, when rendered relatively stilf, straight and smooth, can be flocked and applied to a. backing much more effectively. The sizing may conveniently be done before the pile material is cut, and should involve the use of a size insoluble in the liquid carrying medium. For example, if the latter be kerosene, a Water-soluble size .is employed, for example, gelatin, glue, dextrin, gum-tragacanth, etc., whereas if an aqueous carrying medium is used in the cutting process, a water-insoluble size is employed, for example, pyroxylin, silicate of soda, or resins, natural or synthetic. An additional advantage of the sizing, as herein described, lies in the fact that the manufacturer may both cut and apply to the backing as one unita thread made up of many fine laments, forexample rayon, or, to put it another way, to out and apply as a unit a bundle of filaments. Such bundle may be left either in bundle form, or desized and loosened, as desired. In the usual practice of the invention the cut bres are preferably well dried and loosened before being applied to the backing (fabric, rubber, wood, metal or other firm material) in order that they may be free and separated from one another so as to be readily applied as by sifting to the backing in generally endwise arrangement and with the ends thereof embedded in the adhesive. Any sort of rubber or equivalent adhesive, for example, as already known and used in the art, may be employed to attach the fibres to airubber coated base, but I preferably ernploy a normally liquid heat-treated rubber bonding agent as described and claimed in my application Serial No. 218,971, filed July 13, 1938. Whatever type of adhesive be employed, the fibres are deposited therein, as well known in the art, and thus the heat-treated rubber or other form of rubber adhesive is either permitted to solidify or rendered solid as required so that the bres are firmly held to the backing by vulcanized rubber. After the vulcanizing step, the size, if employed, may be washed out with an appropriate liquid y harmless to the adhesive. If desired, the product l. 'I'he proces of making a pile fabric comprising mixing separated long fibres in a liquid, carf rying said fiuent liquid mass to a cutter, wet-cutting said fibres to a substantially uniform and shorter length, and while the fibres are still wet, dyeing the same, drying the fibres thus cut and dyed and then embedding the ends of the fibres in a liquid adhesive flbre-to-base bonding agent.

2. The processV of making a pile fabric comprising mixing separated long fibre units in a liquid, carrying said fibre-containing liquid to a cutter, wet-cutting said fibres to a substantially uniform and shorter length, and, while the fibres are still wet, dyeing the same, drying the flbres thus cut and dyed, and then embedding the ends of the fibres in a normally liquid adhesive fibre-tobase bonding agent to attach the fibres to a base material.

3. The process of making a pile fabric comprising sizing long fibres, mixing said fibres in a liquid, carrying said fibre-containing liquid to a cutter, wet-cutting said fibres to a substantially uniform and shorter length, and, while the fibres are still wet, drying the fibres thus sized and cut, and then embedding the ends of the fibres in a liquid adhesive fibre-to-base bonding agent to attach the fibres to a base material.

4. The process of making a pile material which consists in wet-cutting unrestrained long bre units of the class described, freely fiotant in a liquid carrying medium, to a flock of shorter and substantially uniform length, drying said cut fibres, and thereafter embedding ends of the fibres in a liquid adhesive fibre-to-base bonding agent to attach the fibres to a base material.

' 5. The process of making a pile material which consists in repeatedly wet-cutting unrestrained separated long fibres of the class described, mixed in and carried by a liquid medium, to a flock of shorter and substantially uniform length, drying said cut fibres and thereafter embedding ends of the fibres in a liquid adhesive Iibre-to-base bonding agent to attach the bres to a base material.

6. The process of making a pile coat having fibres end-embedded in a fibre-to-base bonding agent, comprising mixing separated long fibre units of the class described in a liquid carrying medium to provide a fluent liquid mass containing unrestrained fibre units, passing said fluent mass between cutting edges, wet-cutting said fibres to a flock of shorter and substantially uniform length, drying said cut fibres, and thereafter embedding ends of the fibres in a liquid adhesive fibre-to-base bonding agent to attach the fibres to a base material.

7. The process of making a pile material having fibres end-embedded in a iibre-to-base bonding agent comprising mixing separated long fibre units of the class described in a liquid carrying medium to provide a fiuent liquid mass containing unrestrained fibre units, passing said fiuent mass between cutting edges, wet-cutting said fibres to a fiock of shorter and substantially uniform length, and at some stage of the process dyeing the fibres, and thereafter embedding ends of the fibres in a liquid adhesive flbre-to-base bonding agent to attach the fibres to a base material.

8. The process of making a pile material comprising mixing separated long fibre units in a liquid to provide a fluent liquid mass containing unrestrained bre units, flowing said fluent mass between cutting edges, wet-cutting said fibres to a shorter 'and substantially uniform length and at some stage of the process dyeing and sizing the fibres and thereafter drying the fibres' and embedding ends of the fibres in a liquid adhesive tlbreto-base bonding agent to attach the bres to a base material.

9. The process of making a pile fabric compris- 5 ing mixing separated long fibres in a liquid, carrying said uent liquid mass to a cutter. wet-cutbedding the ends of the bres in a liquid adhesive ibre-to-base bonding agent. i

RAYMOND W. KENT. 

